Posing: Rebeka Francis of Rondonia is among the 27 women battling it out for the title of Miss Bum Bum Brazil

Ms Francis poses with her gold-and-white Rondonia sash (left) and with her bottom toward the camera (right)

All smiles: The competition offers a $22,000 prize and worldwide fame. Above, Tamirys Martins of Amazonas

Ms Martins raises her eyebrow as she poses with her Amazonas sash (left) and pouts at the camera (right)

Bottoms up: It seeks to find the finest example of the female bottom. Above, Bruna Valentim of Rio de Janeiro

Ms Valentim puts her hand on her hip as she poses in her sash (left) before smiling as she turns around (right)

Modelling: In the competition's first stage, representatives from each of the country's states are brought together to witness a public online vote. Above, Ana Paula Costa of Espirito Santo

Ms Costa gazes at the camera in her Espirito Santo sash (left) as her blonde hair tumbles down her back (right)

Tough competition: These are the 27 women who are baring all in a bid to win the title of Miss Bum Bum Brazil

Another hopeful: During the online vote, 15 finalists will be selected. Above, Vivian Cristinelli of Minas Gerais

Ms Cristinelli dons a necklace, large bracelet and earrings for her photographs, with her nails painted white

Battle: The second stage will see a winner chosen by a jury in November. Above, Graziellla Fornazieri of Acre

Ms Fornazieri smiles as she holds hold onto her sash (left) before showing off her thigh tattoo (right)

Sibling rivalry: Now in its fourth year, Miss Bum Bum Brazil has gone from humble beginnings to international fame. Above, Graziellla's sister Rafaella Fornazieri of Alagoas is also competing in the contest

Ms Fornazieri dons a stern expression as she puts her hands on her hips (left) and shows off her bottom (right)

Spin-offs: The competition has had spin-offs in Miami, Japan and for the World Cup. Above, Lucyanne Sanches of Maranhao

Ms Sanches beams as she wears her Maranhao sash (left) before pulling a more seductive face (right)